Frequency Spectrum obtained using my Rust lib (original signal: sine waves at 50, 1000 and 3777 Hz with a little bit of clipping, which results in the noise in the signal)

Frequency Spectrum Analysis with FFT in Rust (library spectrum-analyzer)

One week ago FFT (Fast Fourier Transformation) and frequency spectrum analysis were still a mysterium to me. Because I have a long time planned side project (live beat detection to music) and had some time, I started to make a deep dive into digital signal processing (DSP), including lowpass filters and especially frequency spectrum analysis using FFT. I was a little bit shocked/disappointed by the lack of good ressources and easy to understand Read more…

Effective + Simple Way to Manage & Obtain Multiple Let’s Encrypt Certificate for Different Domains Using a Small Shell Script

Yesterday I faced the problem that I need a convenient way to manage multiple domains on the same host/IP. I have “main” domains with potentially further sub-domains. How can one optimize the retrieval of certificates without writing all the shell commands manually or look ’em up in the shell history? I asked myself this question and came up with this solution, not sure if my solution is ideal but it is effective and Read more…

Screenshot wambo-web.de

Wambo Web is finally online

In the last months I worked on a project called Wambo Web. I already created Wambo, a CLI tool that helps you to easily interpret and convert numbers/bits in any possible way low-level developers often need it (Wambo on crates.io). Now I finally have a Web Version online too. In fact, it is capable of more than the CLI version. It can cope with many input formats (hex, negative, fractional, megabytes, all mixed Read more…

STM32 Nucleo-L4R5ZI Development Board

Setup Jetbrains Clion IDE with STM32CubeMX project for development on STM32 Microcontrollers – Windows

Similar to my previous blog post on programming and debugging STM32 Microcontrollers with Clion IDE on Mac, I want to share a similar easy setup guide for Windows with you. The only difference is that you have to install OpenOCD and ARM GNU eabi Toolchain a little bit different. This tutorial should work for all STM32 based Microcontrollers with a debug interface (JTAG) that is supported by OpenOCD. I used a STM32 Nucleo-L4R5ZI Read more…

STM32 Nucleo-L4R5ZI Development Board

Setup Jetbrains Clion IDE with STM32CubeMX project for development on STM32 Microcontrollers – Mac

I’ve managed to setup programming and debugging a STM32 Nucleo-L4R5ZI development board with Jetbrains Clion IDE on my Mac. If you need the same for Windows, I got your back! This tutorial should work for all STM32 based Microcontrollers with a debug interface (JTAG) that is supported by OpenOCD. I used a STM32 Nucleo-L4R5ZI board. I want to share my findings with you. In this tutorial you have to install Java (required for Read more…

Trace of verbs invoked on sender and receiving side in simple RDMA to RDMA communication. The trace was captured for "RXE to RXE" device communication using the tool "ib_send_bw" from the "rdma perftools" project.

Trace of Verb Calls in RDMA Communication in Linux (How does RDMA communication work)

For an uni project at TU Dresden I had to work with the RDMA implementation inside Linux. I think that RDMA in Linux is terribly poorly documented and there are only a few good resources. I want to share with you the findings I made that I wish I had at the beginning. A few findings to better understand how the RDMA stack works and what an RDMA connection actually is. I can’t Read more…